Chemistry questions and answers

Chemistry Questions and Answers

Learn more about the properties, composition, and structure of substances (elements and compounds) with these Chemistry questions and answers. This Test can be used by students preparing for Chemistry in JAMB, WAEC, NECO or Post UTME.

2,736.

Which of the following combinations of conditions may increase the rate of a chemical reaction?

A.

Decrease in temperature, increase in concentration of the reactants

B.

Increase in temperature, addition of a catalyst, decrease in the surface area of the reactants

C.

Increase in temperature, increase in concentration, addition of a catalyst and increase in the surface area of the reactants

D.

Decrease in temperature concentration and surface area of the reactants

E.

Additionof a catalyst and in the absence of light

Correct answer is C

Increase in temperature, increase in concentration, increase the rate of chemical reaction

2,737.

What weight of sodium hydroxide is required to make 500 cm3 of 0.2 M solution?

(Na = 23, O = 16, H = 1)

A.

40 g

B.

20 g

C.

10 g

D.

4 g

E.

2 g

Correct answer is D

No explanation has been provided for this answer.

2,738.
2,740.

When copper powder is heated with concentrated sulphuric acid, the gas produced is?

A.

hydrogen sulphide

B.

sulphur dioxide

C.

sulphur trioxide

D.

hydrogen pentasulphide

E.

sulphur pentoxide

Correct answer is B

No explanation has been provided for this answer.